Dojo.js AMD Loader-TypeError：无法将未定义转换为对象

Question

I looked for duplicate questions, but did not find one exactly. This is related to Dojo require() and AMD (1.7) , but I will ask in the form of a question. The question is, why am I getting this error and why is dijit showing '3' in firebug?

The JSP Page

<script type="text/javascript" src="<%= request.getContextPath() %>/js/dojoConfig.js"></script>
<script type="text/javascript"
src="http://xxxxxxxxxxxxx.com/dojo/1.7.2/dojo/dojo.js.uncompressed.js"></script>
<script type="text/javascript" src="<%= request.getContextPath() %>/js/reviewframe.js"></script>

dojoConfig.js

var dojoConfig = {
// Use the Asynchronous AMD loader.
// --------------------------------
async : true,
// Use debug.
// --------------------------------
isDebug : true,
// Parse the html on load for dojo rendered elements.
// Don't Parse on Load. I'm calling it manually in my main pageLoad.
// --------------------------------
parseOnLoad : false,
};

reviewframe.js (My 'main')

require(
[ "dojo", "dijit", "dojo/parser", "js/XYDialog.js",
"dijit/layout/ContentPane", "dojox/image/LightboxNano", "dojo/ready",
"dojo/domReady!" ],
function(dojo, dijit, parser, XYDialog) {

XYDialog.js

define([ "dojo", "dijit", "dijit/form/Button", "dijit/TooltipDialog",
    "dijit/form/DropDownButton", "dijit/form/FilteringSelect" ], function(
    dojo, dijit) {

I set a breakpoint on the define above in XYDialog.js. I hit continue and I get this error in the console:

console

focus.js line 382
TypeError: can't convert undefined to object [Break On This Error]  ...attr] = typeof singleton[attr] == "function" ? lang.hitch(singleton, attr) : sin...

If I set a Firebug breakpoint in focus.js right before that line, I see that dijit is the number 3. Why? I have seen this before in other places where the javascript or modules I require end up being the number 3.

EDIT: OMG, I closed Firefox and loaded the page w/o firebug. It works! Then I opened firebug, cleared all breakpoints and it works again. Sheesh.

Follow up question: Can breakpoints in firebug screw up the AMD loader? It is asynchronous after all. Your breakpoint may introduce a timing issue...

Answer 1

There are two issues here:

1. You are loading an AMD module using the file name rather than the module ID (XYDialog.js), so it is being treated and loaded as a non-AMD module. You should either put it in a logical package, or define the path in your config, eg:

   file structure:

    /js/foo/XYDialog.js /js/dojo/dojo.js 

   code:

    // reviewframe.js (My 'main') require( [ "dojo", "dijit", "dojo/parser", "foo/XYDialog", 

2. The cryptic code "3" usually refers to an incorrect path to a package. I believe the first issue, combined with Firebug, may be inconsistently giving you this error.

See the note under http://www.sitepen.com/blog/2012/10/31/debugging-dojo-common-error-messages/#incorrect-package-path (this article in general is one we wrote that will help you identify the cause of the most common error messages when using Dojo and AMD).

Answer 2

重新启动Firefox并清除Firebug中的断点。